Researchers asked 61 volunteers to tally the number of bites they took each day and pledge to take 20 percent to 30 percent fewer bites over the next four weeks. They also tracked their intake of liquids other than water.

The 41 participants who kept their vow lost about four pounds during that month -- about what the U.S. Centers for Disease Control and Prevention recommends for healthy weight loss.

The Brigham Young University study was published recently in the journal Advances in Obesity, Weight Management & Control.

"This study confirms what we already knew: Consuming less food makes a difference," lead author Josh West, an assistant professor of health science, said in a university news release. "We're not advocating people starve themselves, what we're talking about is people eating less than they're currently eating."

Further research is needed to determine if this approach leads to long-term weight loss, said study co-author Ben Crookston, an assistant professor of health science.

"We felt pretty good about how much weight they lost given the relatively short span of the study," he said in the news release. "Now we need to follow up to see if they keep it off, or if they lose more weight."

The researchers said counting bites could offer an effective, affordable method of weight loss for the 70 percent of Americans who are overweight.

"We're consuming considerably more calories than we did a generation ago or two generations ago; at the same time we're much less active," Crookston said. "Even a 20 percent reduction in bites makes a difference."